Electrode release for arc lamps



F. C. COATES ELECTRODE RELEASE FOR ARC LAMPS Nov. 14, 1939.

Original Filed Aug. 27, 1938 2 Sheets-Sheet 1 INVENTOR. fiSLfil/VG 6. 604x55 BY 14% ATT Nov. 14, 1939. F. c. COATES ELECTRODE RELEASE FOR ARC LAMPS v Original Filed Aug. 27, 1938 2 Sheets-Sheet 2 Mm R u I z i mm Q em m mm in V llllllllllxlllllll L vs 7 mm m wuwm INVENTOR fizzy/ma 6. 60472:;

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Patented Nov. 14, 1939 UNITED STATES PATENT OFFICE ELECTRODE RELEASE FOR ARC Fielding 0. Coates, Los Angeles. Calif., assignmto Mole-Richardson 00., Los Angeles, Calif., a limited partnership of California 2; 7 Claims.

My invention relates to an improved electrode release for are lamps and has particular utility when employed with arc lamps of the type in J which the electrode is continuously rotated and advanced during operation.

This application is a division of my copending application, Serial No. 227,142, filed August 27, 1938, describing and claiming an improved electrode release device for are lamps.

In arc lamps of the type for which the subjectmatter of this invention is adapted for use, either one or both electrodes are continuously rotated during the operation of the lamp. An example of this type of arc lamp is disclosed in the United States patent to Elmer C. Richardson, No.

The principal objection to lamps of this type has been the difliculty in removing spent electrodes and replacing them with new ones. This difliculty has been due to the fact that no means was available to relieve the high pressure exerted on the electrode by the electrode feeding wheels or gears.

Release mechanisms have been devised to free 'the electrode, but none have thus far provided either or both manual or automatic means for effecting the positive disengagement of the release and the re-engagement of the feeding means whenever the lamp is started up after a change of electrodes. A disadvantage in the present types of releases lies in the tendency for the release mechanism to become locked in the released position. I

It is therefore a primary object of my invention to provide a simple and expedient means for re leasing an electrode to permit ready replacement thereof, wherein said releasing means may be positively operated to a disengaged position either manually or, preferably, automatically when the arc lamp is put into operation.

It is an additional object of my invention to provide a means for releasing the electrode which will automatically effect the re-engagement of the feeding means whenever the lamp is replaced 4 in operation, even though the workman should inadvertently fail to return the releasing mechanism to the off position.

It is also an object of my invention to provide a release mechanism of the character set forth in which the force tending to return said mechanism to the non-released position is at its greatest when in a position to release the electrode.

Other objects and advantages of my invention ggz'will b'e apparent from a study of the following specifications, read in connection with the accompanying drawings, wherein:

Fig. 1 is a longitudinal section illustrating the feeding and electrode releasing mechanism employed with one of the electrodes in a lamp of the type described in the United States patent to Richardson, No. 2,060,347, issued November '10, 1936;

Fig. 2 is a transverse section taken along the line 11-11 of Fig. 1 illustrating the details of construction of the manual control device employed with the release mechanisms of my invention;

Fig. 3'is a transverse sectional view taken substantially along the line III-III of Fig. 1 illustrating the details of construction of one form of release mechanism of my invention;

Fig. 4 is a fragmentary longitudinal section similar to the electrode release portion of Fig. 1 and illustrating details of construction of an alternative form of release device of my invention;

Fig. 5 is a plan view of the manual control device of my invention with parts broken away to show the interior construction.

The electrode feeding means to which the release device of my invention is applied is illustrated in Fig 1 (it being understood that Fig. 1 illustrates only that portion of the type of arc lamp previously referred to which includes the feeding mechanism for one of the plurality of electrodes employed, the other electrode mecha nism associated therewith, and lamp housing being deleted) as including an electrode [5 carried in a gear housing 16 which encloses the driving and feeding mechanism therefor.

Power for rotating and feeding the electrode I 5 is suppliedthro'ug'h a suitable shaft H to which is affixed a bevel gear [8 arranged to mesh with another bevel gear [9 suitably attached to an electrode carrier or sleeve 29 in which the electrode 15 is inserted. The sleeve 20 is suitably journaled for rotation as by means of ball bearings 2| and 22 interposed between the sleeve 20 and the housing 16.

A spur gear 23 is suitably attached to the rotatable sleeve 20 and is arranged to engage supplementary gearing (not shown), which gearing also engages another spur gear 24. The spur gear 24 is'rotatably supported by the rotatable sleeve 20 so that it may rotate independently of the sleeve 20 upon the exterior thereof.

The spur gear 24 has teeth 25 formed on the forward face thereof, which teeth are arranged in a spiral or scroll form. A pair of electrode feeding wheels 25 and 21 are provided which may be formed with gear teeth arranged to mesh with the teeth 25 of the scroll gear and to also engage the sides of the electrode [5.

In order to properly locate and support the electrode feeding wheels 26 and 21, a face plate 28 is provided which is securely attached in any suitable manner to the rotatable sleeve 28 and has provided thereon bearing brackets 39 and 3| through which suitable shafts or axles 32 and 33 are passed. The shafts 32 and 33 are employed as axle members for the feeding wheels 26 and 27.

Bearing brackets 38 and 3! are slotted as indicated at 34 and 35 so that the axles 32 and 33 may move inwardly and outwardly with respect to the electrode l5. Resilient means (preferably tension springs as 36 and 3'!) are coupled to the shafts 32 and 33 in the manner illustrated in Fig. 3 so as to urge the wheels 26 and 2-1 inwardly to forcibly engage the electrode l5,

In operation, the sleeve 28 is rotated by'power supplied through the shaft H in such direction as to cause the electrode [,5 to rotate in thedirection indicated in Fig. 1 by an arrow 38. The gearing interposed between the spur gears 23 and 24 and the direction in which the spiral teeth 25 are developed is so arranged as to cause the electrode feeding wheels 26- and 2'! to rotate in opposite directions and feed the electrode I5 forwardly as indicated by arrow 39 in Fig. 1.

A heat absorber and radiator 40 is suitably secured to the housing l6 and arranged to shield the mechanism previously described from the flame of the are so as to prevent raising the temperature of the aforementioned working parts to an undesirable value.

Although the foregoing description is directed to a common form of feeding and driving mechanism for the electrode of an arc lamp, it is included herein to facilitate the understanding of the way in which the release mechanism of my invention operates. the release mechanism of my invention as being applied to the type of lamp mechanism just described, it is to be understood thatthis mechanism may also be readily applied to other types of electrode rotating and feeding devices.

It will be readily seen from the foregoing that in order to remove the electrode l5 from the sleeve 20 through which it is inserted, it is necessary to disengage the feeding wheels 26 and 21 and that such disengagement must be accomplished by overcoming the force of the tension springs 36 and 31 urging said wheels toward the electrode l5. It is common practice to make the springs 36 and 3'! very strong in order that the electrode feeding wheels 26 and 2'! may positively engage the electrode l5. In view of the strength of the springs 36 and 3'! it is a. difficult task to disengage the feeding gears from the: electrode unless a control means for so doing is provided.

The control means for accomplishing the above includes an internal sleeve 45 which is interposed between the electrode l5 and the driving sleeve 29 and arranged to slide freely therebetween. The internal sleeve 45 is extended forwardly past the electrode feeding wheels 26 and 27 and terminates in a release member 46 suitably attached thereto. Thesleeve 45 is provided with slots 41 and 48 (Fig. 3) through which the electrode feeding wheels 26 and 21 pass so as to engage the electrode [5. 1 1 g The release member 46 is illustrated in Figs. 1 and 3 and includes a transverse portion 58 in which is provided a suitable opening 5| for attachment to the sleeve 45. Extending oneither of studs I69, H9, H5, and H2.

While I have illustrated side of the electrode 15 and attached to the transverse portion 58 is a pair of longitudinal portions 52 and 53. The longitudinal portions 52 and 53 are spaced apart a sufficient distance to straddle or pass over the bearing bracket structures 30 and 3|.

I provide on each of the longitudinal portions 52 and 53 a pair of rollers Il86 and l[l1l08 which are pivotally mounted thereon by means Each of the studs is provided with an upset head for retaining the roller associated therewith. In order that these rollers may operate as a wedging means to stretch the tension springs 36 and 31 and release the electrode feeding wheels 26 and 21 from the electrode l5, I provide enlargements H3 on each of the shafts 32 and 33 in a position to be engaged by the rollers positioned adjacent thereto.

Reference to Fig. 1 will show that movement of the sleeve 45 to the left as illustrated in Fig. 1 will cause the release member 48 attached thereto to move to the left and cause the rollers I85, I86, I01 and I08 to engage the corresponding enlarged portions H3 of the shafts 32 and 33 in a wedging manner to force the shafts 32 and 33 outwardly from the electrode l5 thereby disengaging the feeding wheels 26 and 27 from said electrode. In order that the sleeve 45 may be moved to the left whenever it is desired to release the electrode I5 by disengaging the feeding Wheels 26 and 21, I extend the sleeve 45 rearwardly a sufiicient distance to extend beyond the edge of the previously mentioned bevel gear l8 to provide clearance between said gear and a collar 18 which is attached to the slidable sleeve 45.

The collar 18 may be adjustably attached to the sleeve 45 as by means of screw threads 19 and locked in whatever position is desired by means of a lock nut 88. The collar 18 includes a cylindrical portion 8! and a flange portion 82 of a diameter larger than the cylindrical portion 8| and located rearwardly with respect thereto.

A handle mechanism 83 is provided which includes a handle 84 adapted to be used by an operator in releasing the electrode I5 from the electrode feeding mechanism and a plate portion 85 formed integrally with the handle 84. The plate portion 85 is provided with a central opening 86 adapted to slide over the cylindrical portion 8! of the collar '88 and provided with three substantially equally spaced holes 81, 88 and 89 of such diameteras to loosely accommodate steel balls 98, 9| and 92. The holes 81, 88 and 89 are spaced from the center of the sleeve 45 a distance such that the balls included therein may rest upon the cylindrical portion 8| of the collar 18.

A retainer 93 is suitably attached to the plate portion 85 of the handle mechanism 83 and cooperates with the flange portion 82 of the collar 18 to confine the lowermost steel balls 9| and 92. This complete mechanism is enclosed in a casing 94 which is attached to the housing l6 as by screws 95, and which provides an inwardly projecting rib 96. The rib 96 may be of trapezoidal cross section, providing an essentially radial surface 91 adjacent the upper steel ball and a sloping surface 98 for providing strength and rigidity to the member 96.

As best illustrated in Figs. 1 and 5, the radial surface 91 is semi-helical in shape so as to provide a maximum clearance between said surface and the flange 82 at the right end of the flange 82, as viewed in Fig. 2, and a minimum clearance therebetween at the left hand end. The radial surface 91 cooperates with the flange 82 to confine the upper ball therebetween. A suitable slot 99 is provided in the housing 94 to allow the handle 84 to extend therethrough.

It will be seen that rotation of the handle mechanism 84 to the left or counterclockwise, as viewed in Fig. 2, will cause the balls confined therein to rotate with the handle assembly. As the upper ball 90 moves between the flange 82 and the helical surface 91 of the projection 96 the space therebetween for said ball becomes progressively smaller so that a wedging action is developed to force the collar I8 and the sleeve 45 attached thereto to the left, as viewed in Fig. l.

The sleeve 45 is coupled to the electrode feeding mechanism in the manner previously described so that movement of the slidable sleeve 45 to the left will release the feeding mechanism from the electrode I5. Conversely, a movement of the handle 84 to the right after the sleeve 45 has been moved to the electrode releasing position will move the upper ball 90 into that portion of the space between the flange 82 and the radial surface 91 which provides the greatest space therebetween.

The amount of rearward movement imparted to the sleeve 45 by a leftward movement of the handle 84 is preferably limited to an amount which will cause the rollers I05, I06, I01 and I08 to move the feeding wheels 26. and 21 out of engagement with the electrode but not sufficiently far to place the axes of these rollers in alignment with the axes of the shafts 32 and 33.

It will be apparent that as long as the rollers which are carried by the release members 46 are disposed to the front side of a dead-center position, the force of the tension springs 36 and 31 urging the feeding wheels 26 and 21 toward each other will develop a horizontal force component tending to move the release member 46 to the right, as illustrated in Fig. 1. Whenever the control handle 84 has been moved to the right so as to remove the leftward force on the sleeve 45, the force resulting from the interaction of the springs 36 and 31 and the release member 46 will move the sleeve 45 forwardly in correspondence with the movement of the handle 84 to the right so as to place the electrode feeding mechanism into operative engagement with the electrode I5.

This form of control mechanism is automatically releasable and is responsive to rotation of the electrode l5 to effect this release. Whenever the electrode I5 and the slidable sleeve 45 associated therewith is rotated in the direction of the arrow 38, the flange 82 of the collar 18 will be rotated therewith. Inasmuch as the ball 90 is confined between the flange 82 and the helical rib 96, rotation of the flange 82 will roll the ball between said flange and said rib toward the open end of the space therebetween. This allows the sleeve 45 to slide forwardly to engage the electrode feeding wheels 26 and 21 in a manner previously described.

The electrode release mechanism of my invention is therefore constructed in such a manner and provided with such a control mechanism that it is impossible for an operator of a lamp equipped with this device to inadvertently operate the lamp without the feeding mechanism functioning. This is due to the fact that, as hereinbefore described, resumption of the operation of the lamp after installation of a new electrode will automatically cause the electrode release mechanism to be disengaged from the feeding mechanism and will permit re-engagement of the feeding wheels with the electrode.

In the modification illustrated in Fig. i the release member 46 has been simplified to provide a release member 4611 comprising a plate member extending transversely of the axis of the sleeve 45 and secured thereto in any suitable manner. Cooperating with the release member 4% is a system of bell cranks I I5 which includes bell cranks II 6 and II '1 pivotally secured to the bearing bracket 30 and a similar pair of bell cranks pivotally secured to the bearing bracket 3| (not shown). Pivotal mounting of the bell cranks II5 may be obtained by providing suitable projections I20 formed on the bearing brackets 30 and 3I. The bell cranks are preferably angular in shape and are pivotally secured in the manner described at one end of one of the angle legs, the point adjacent the junction between the two legs being provided with a circular opening I2I encircling the protruding ends of the shafts 32 and 33. The other lever arm portions of the bell cranks I I5 are arranged to be engaged by the release member 4622 which extends in overlapping relation relative to the bell cranks II5. Movement of the release member 4512 to the left in response to a sliding movement of the sleeve 45 connected thereto will cause pivotal movement of the bell cranks about their pivot points and the engagement of the angle portions of these bell cranks with the shafts 32 and 33 will cause the shafts to move outwardly with respect to the electrode I5 and effect the release thereof in a manner previously set forth.

In this form of the invention it should be noted that the points of engagement between the lever arm portions of the bell cranks H5 with the release member 46?) lies substantially on a line between the shafts 32 and 33. This arrangement allows a compact arrangement of parts permitting the heat shield 40 to be located closely adjacent the electrode release mechanism so as to provide an extremely compact structure.

It will be noted that I have provided a release device in which the restoring force tending to restore the feeding mechanism to an electrode engaging position increases as the device is op erated in a direction to release the electrodes. In other words, whenever the slidable sleeve 45 is moved to the left to effect the release of the electrode 55, said release is accomplished by overcoming the force of the tension springs 36 and 31. The force exerted by these springs necesappears during a release operation as a force tending to restore the slidable sleeve 35 to a non-released position.

Inasmuch as the mechanical advantage pro-- vided between the sleeve 45 and the springs 31 is of the constant ratio type, and inasmuch as the force exerted by the springs increases as the springs are stretched during the release operation, it follows that the force tending to restore the sleeve 45 to the non-released position must increase as the sleeve is moved toward the released position.

This differs from the present construction that the mechanical advantage provided between the sleeve and the springs increases in those in present use as the sleeve is moved to a released position. This increase in mechanical advantage overcomes the increased force from the springs with the result that the restoring force on the sleeve becomes less and less as the sleeve is moved toward the released position. It will be seen, in summary, that the device of my invention eliminates a major disadvantage in the present construction in that those in present use, in which the restoring force reduces as the feeding mechanism is released, tend to allow the feeding mechanisms to become locked in the disengaged position, thereby requiring repairs to said mechahisms and a consequent loss of time and money.

It will also be seen that I have provided a release mechanism for electrodes employed in an arc lamp which is provided with a control means located externally of the lampmechanism and in which operation of said control means may be directed to either release the electrode for replacement or engage the feeding means with a new electrode.

While I have shown and described the preferred embodiment of my invention, I do not desire to be limited to any of the details of construction shown or described herein, except as defined in the appended claims.

I claim:

1. In an arc lamp, the combination of: an electrode; a rotatable electrode carrier supporting said electrode for rotation about its longitudinal axis; electrode feeding wheels for engaging said electrode; mounting means for mounting said feeding Wheels on said carrier for movement out of engagement with said electrode and into electrode engaging position; a release member engageable with said mounting means for moving said feeding wheels out of engagement with said electrode; a sliding sleeve interposed between said electrode and said carrier for rotation therewith and for operating said release member; a flange on said sleeve; a stationary flange disposed at an angle and spaced from said flange on said sleeve; a rolling member confined in said space between said flanges; and a manually operable means for urging said rolling member toward the apex of said angle for sliding said sleeve to move said feeding Wheels out of engagement with said electrode.

2. In an arc lamp, the combination of: an electrode; a rotatable electrode carrier supporting said electrode for rotation about its longitudinal axis; means for normally rotating said carrier in one direction; electrode feeding wheels for engaging said electrode; mounting means for mounting said feeding wheels on said carrier for movement out of engagement with said electrode and into electrode engaging position; a release member engageable with said mounting means for moving said feeding wheels out of engagement with said electrode; a slidable sleeve coupled to said release member and carried by said electrode carrier so as to be rotatable therewith; a flange portion secured to said slidable sleeve; a stationary flange spaced from said flange on said sleeve and disposed at an angle relative thereto with the apex of said angle disposed in a direction opposite to the normal rotation of said flange; a rolling member confined in said space between said flanges; and a manually operable means for urging said rolling member toward said apex of said angle for sliding said sleeve to move said feeding wheels out of engagement with said electrode.

3. In an arc lamp, the combination of: an electrode; a rotatable electrode carrier supporting said electrode for rotation about its longitudinal axis; electrode feeding wheels for engaging said electrode; mounting means for mounting said feeding Wheels on said carrier for movement out of engagement with said electrode and into electrode engaging position; a release member engageable with said mounting means for moving said feeding wheels out of engagement with said electrode; a sliding sleeve interposed between said electrode and said carrier for rotation therewith and for operating said release member; a flange on said sleeve; a stationary flange disposed at an angle and spaced from said flange on said sleeve; a rolling member confined in said space between said flanges; a plate member disposed between said flanges and encircling said sleeve; a plurality of openings in said plate member, one of said openings comprising a cage for said rolling member; a bearing member carried in each of the openings in said plate member for holding said plate member in a fixed lateral position relative to said sleeve; and handle means secured to said plate member and manually operable to rotate said plate member about said sleeve to move said rolling member toward the apex of said angle for sliding said sleeve and moving said feeding wheels out of engagement with said electrode,

4. In a holder for supporting an electrode, the combination of a plurality of rotatable feeding wheels; axles mounting said feeding wheels for rotation; means mounting said axles for movement toward and away from said electrode; re silient means for urging said feeding wheels into engagement with said electrode; a movable release member; a plurality of rollers pivotally supported by said release member in a position disposed between the axles associated with adjacent feeding wheels for engaging said axles to force said feeding wheels out of engagement with said electrode; and means for moving said release member.

5. In an electrode holder, the combination of: a rotatable electrode carrier; a plurality of rotatable feeding wheels; axles mounting said feeding wheels for rotation; means mounting said axles on said carrier for movement toward and away from said electrode; resilient means for urging said feeding wheels into engagement with said electrode; a movable release member; a plurality of rollers pivotally supportedbysaid release member in a position disposed between the axles associated with adjacent feeding wheels for engaging said axles to force said feeding wheels out of engagement with said electrode; and a control means coupled to said release member and responsive to a manual operation for moving said feeding wheels out of engagement with said electrode and responsive to rotation of said electrode carrier for moving said rollers out of engagement with said axles to allow said resilient means to move said feeding wheels into electrode engaging position.

6. In a holder for supporting an electrode, the combination of: a plurality of rotatable feeding wheels; axles mounting said feeding wheels for rotation; mounting means mounting said axles for movement toward and away from said electrode; resilient means for urging said feeding wheels into engagement with said electrode; a plurality of hell cranks, each comprising a lever portion and an arm portion secured to said lever portion and being angularly disposed relative thereto; a pivot point in the end of said arm portion; stationary pivot means engaging the ends of said arm portions and mounting each of said bell cranksfor pivotal movement upon said mounting means; means pivotally connecting each one of said bell cranks to one end of each of said axles at the junction of said arm portion and said lever portion; a movable release member engageable with the end of each of said lever portions for rotating said bell cranks about said pivot points to force said feeding wheels out of engagement with said electrode; and means for moving said release member into engagement with said lever portions.

7. In a holder for supporting an electrode, the combination of: a rotatable electrode carrier; a plurality of rotatable feeding wheels; axles mounting said feeding wheels for rotation; means mounting said axles on said carrier for movement toward and away from said electrode; resilient means for urging said feeding wheels into engagement with said electrode; a plurality of bell cranks, each comprising a lever portion and an arm portion secured to said lever portion and being angularly disposed relative thereto; a pivot point in the end of said arm portion; stationary pivot means engaging the ends of said arm portions and mounting each of said bell cranks for pivotal movement upon said electrode carrier; means pivotally connecting each one of said bell cranks to one end of each of said axles at the junction of said arm portion and said lever portion; a movable release member engageable with the end of each of said lever portions for rotating said bell cranks about said pivot points to force said feeding wheels out of engagement with said electrode; and a control means coupled to move said release member and responsive to a manual operation for moving said feeding wheels out of engagement with said electrode and responsive to rotation of said electrode carrier for moving said release member out of engagement with said bell crank lever portion to allow said resilient means to move said feeding wheels into an electrode engaging position.

FIELDING C. CQATES. 

